Remove "wlcna:migrate_to_news_article"
Remove "wlcna:migrate_to_news_article"

This was introduced in
https://github.com/alphagov/whitehall/commit/e03c57040aadadc27eb8479216e
b3594dac9e0f1#diff-72f2ad8ed3451f515da3be375f3f5b89 and was run on
production, so can be removed.

alphagov/whitehall,alphagov/whitehall,alphagov/whitehall,alphagov/whitehall